UKCBAMCalculator

UK CBAM, from 1 January 2027

UK CBAM calculator: the carbon charge on your imports

From 1 January 2027 an importer of CBAM goods pays a charge on the emissions embodied in them. HMRC's illustrative 2027 rates run from £1.45 per tonne of CO2e for fertiliser to £9.79 for aluminium. Enter your goods to see the charge, less any carbon price already paid.

Source: UK CBAM rules and rates: every row, with its source

Your figures

Default: 2.434, HMRC's default value for anhydrous ammonia (CN 28141000). Look your CN code up on HMRC's default values pages.

Only a qualifying carbon pricing scheme, with the verification documents HMRC asks for, counts towards carbon price relief.

The result

Your CBAM liability
£3,529.30
Illustrative 2027 CBAM rate for the sector, per tCO2e
£1.45
Embedded emissions (tCO2e)
2,434
CBAM charge before relief
£3,529.30
Carbon price relief
£0.00
CBAM liability per tonne of goods
£3.53
Registration
Over the £50,000 threshold: you must register with HMRC

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  • Free, and no obligation
  • Read and answered by Joe himself, never passed to a firm or a list
  • No tax, legal or customs advice: a call to frame your options

What this is based on

  1. The rates. HMRC's illustrative 2027 rates per tonne of CO2e: iron and steel £9.69, aluminium £9.79, cement £8.78, fertiliser £1.45, hydrogen £9.24. They are illustrative: the rate for each quarter is worked out from the preceding quarter's average UK ETS price. HMRC: illustrative CBAM rates and worked example
  2. How a rate is built. HMRC's worked example for cement: the Q3 2026 average UK ETS price of £58.15, times one minus the sector's 87.1% baseline free allocation times the 97.5% phase-out reduction factor, gives £8.78 per tCO2e. HMRC: illustrative CBAM rates and worked example
  3. Charge, relief and liability. HMRC: the CBAM charge is the imported embodied emissions times the CBAM rate; carbon price relief is the relevant embodied emissions times the effective carbon price; the liability is the charge less the relief. The calculator never lets relief exceed the charge. HMRC: CBAM policy summary
  4. Default values. Where you have no verified supplier data, HMRC publishes a default value per CN code, in tonnes of CO2e per tonne of product: 2.434 for anhydrous ammonia, for example. HMRC: fertilisers default values
  5. Registration. HMRC sets the registration threshold at £50,000 of CBAM goods, tested backward over the preceding 12 months and forward over the next 30 days. The calculator applies the backward test only. HMRC: CBAM policy summary

This calculator applies HMRC's published illustrative 2027 CBAM figures to what you enter; it is not tax, customs or legal advice, and HMRC's return is the figure you pay. An enquiry sent through the form is read and answered by Joe, who runs this site; no firm receives it.

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  • Free, and no obligation
  • Read and answered by Joe himself, never passed to a firm or a list
  • No tax, legal or customs advice: a call to frame your options

UK CBAM rates and rules, as HMRC publishes them

Last updated

Each figure the calculator and this page rest on, with the government page it was read from.

Every figure is read from HMRC, HM Treasury or DESNZ through this site's fetch service and dated. Trade press and consultants' guides are used for nothing.

FigureValueWhere it comes fromSource
Illustrative 2027 CBAM rate, iron and steel£9.69 per tCO2eHMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Illustrative 2027 CBAM rate, aluminium£9.79 per tCO2eHMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Illustrative 2027 CBAM rate, cement£8.78 per tCO2eHMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Illustrative 2027 CBAM rate, fertiliser£1.45 per tCO2eHMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Illustrative 2027 CBAM rate, hydrogen£9.24 per tCO2eHMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Average UK ETS price, Q3 2026£58.15 per tCO2eHMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Free allowance phase-out reduction factor, 202797.5%HMRC illustrative rates HMRC: illustrative CBAM rates and worked example
Registration threshold£50,000 of CBAM goodsHMRC CBAM policy summary HMRC: CBAM policy summary
Time to register once liable30 daysHMRC CBAM factsheet HMRC: CBAM factsheet
Records kept after the accounting period6 yearsHMRC CBAM policy summary HMRC: CBAM policy summary
UK ETS auction reserve price, 2027£29.01DESNZ UK ETS markets DESNZ: UK ETS markets (auctions, reserve price)

Cite this page

“UK CBAM rates and rules, as HMRC publishes them”, UK CBAM Calculator, https://ukcbamcalculator.co.uk/ (updated 2026-10-28). Every figure is read from HMRC, HM Treasury or DESNZ through this site's fetch service and dated. Trade press and consultants' guides are used for nothing.

The detail

Sourced, dated, kept current.

UK CBAM rates for 2027: HMRC's illustrative figures by sector

HMRC's illustrative 2027 UK CBAM rates per tonne of CO2e for iron and steel, aluminium, cement, fertiliser and hydrogen, and how each rate is worked out.

UK CBAM default values: HMRC's emissions per tonne by CN code

HMRC's UK CBAM default values in tonnes of CO2e per tonne of product, for the first CN codes on each sector's list, and how to use them in the calculator.

UK CBAM registration: the £50,000 threshold and the two tests

When a UK importer must register for CBAM: the £50,000 threshold, the backward and forward tests, 30 days to register, and the records HMRC expects kept.

The questions we get

How is the UK CBAM charge calculated?

HMRC: the charge is the imported embodied emissions times the CBAM rate, carbon price relief is the relevant embodied emissions times the effective carbon price paid, and your liability is the charge less the relief.(HMRC: CBAM policy summary)

What are the UK CBAM rates for 2027?

HMRC's illustrative 2027 rates per tonne of CO2e are £9.69 for iron and steel, £9.79 for aluminium, £8.78 for cement, £1.45 for fertiliser and £9.24 for hydrogen. The rate for each quarter follows the preceding quarter's average UK ETS price.(HMRC: illustrative CBAM rates and worked example)

When do I need to register for UK CBAM?

When the value of CBAM goods you import reaches £50,000 over the preceding 12 months, or you expect it to within the next 30 days. HMRC says you then ordinarily have 30 days to register.(HMRC: CBAM policy summary)

Is this my exact CBAM bill?

No. It applies HMRC's illustrative 2027 rates to the figures you enter. Your actual rate depends on the quarter, and your emissions on your goods' verified data or HMRC's default values.(HMRC: illustrative CBAM rates and worked example)

Sources

This site's own datasets, every figure quoted from its source and dated:

  1. HMRC: illustrative CBAM rates and worked example
  2. HMRC: CBAM policy summary
  3. HMRC: CBAM factsheet
  4. DESNZ: UK ETS markets (auctions, reserve price)
  5. HMRC: iron and steel default values
  6. HMRC: aluminium default values
  7. HMRC: cement default values
  8. HMRC: fertilisers default values
  9. HMRC: hydrogen default values

The question this page is here to answer

What does UK CBAM compliance cost: software subscriptions, consultancy and chamber services?

Your sector, tonnes and emissions per tonne. The rates come from HMRC's own illustrative figures.

Answered by Joseph Ellul, which reads every enquiry this page takes.

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